[Ruud-v-A]

We are actually using Docker for generating the virtualenv that we ship and running tests now. The motivation for doing this is being able to control the environment; we can run tests and build a package on CI, and we can build the same package locally when CI is down. We don’t use Docker in production.

It is not clear to me how Docker solves the issue of pinning dependencies; I would rather have a file that states the exact version of every package to install, than an opaque blessed container image that has some versions installed, and I do want to have the versions used under source control. Generating the image would not be reproducible (in the sense of having the same Python files inside it) without pinning versions somewhere anyway, right? Or am I missing something obvious?